P1035: COUNTRY DIFFERENCES IN THE BURDEN OF PATIENTS WITH HYPEREOSINOPHILIC SYNDROME IN EUROPE
Authors: J. Hwee, N. Kwon, R. Alfonso-Cristancho, L. Baylis, G. Requena, S. Du, A. Khanal, L. Huynh, M. S. Duh, R. W. Jakes
Journal: HemaSphere (2022)

Background: Hypereosinophilic syndrome (HES) is a group of rare blood disorders characterized by peripheral eosinophilia that can lead to tissue and organ damage. Diagnosis and management of HES can be challenging owing to differences in patient characteristics, disease characteristics and clinical manifestations. At present, there is limited information available on the burden of HES in Europe. Aims: To describe real-world patient demographics, disease characteristics, clinical manifestations, treatment patterns, and clinical outcomes for patients with HES across Europe. Methods: This retrospective chart review study included patients ≥6 years old with a confirmed diagnosis of HES and ≥1 year of follow-up data from index (first physician encounter: Jan 2015–Dec 2019). Chart review was conducted by physicians in 5 European countries (France, Germany, Italy, Spain, and the United Kingdom [UK]). Data from a similar number of patients were reviewed and included across each country. Patients could be newly diagnosed during the patient identification window or could be diagnosed prior to their index date, allowing for the inclusion of patients with differing disease duration and organ involvement. Patient demographics, disease characteristics, clinical manifestations, treatment patterns, and clinical outcomes were summarized and described across the overall population and separately by country. Results: Overall, 280 patients were included in the study. Most patients were male (65.0%), with the highest proportion of male patients in Spain (73.1%) and France (75.4%). The majority of patients (55.4%) had idiopathic HES. The most common comorbidity overall was asthma (45.0%); however, in the UK, anxiety/depression was more common than asthma (51.6% vs 41.9%), and in France, both anxiety/depression and hypertension were more common than asthma (37.7% vs 23.0% and 36.1% vs 23.0%, respectively) (Table). Most patients (88.6%) were newly diagnosed with HES during the study time frame. Italy had the highest proportion of patients (17.3%) diagnosed prior to the study while Germany had the lowest (1.9%). The overall mean (standard deviation [SD]) number of distinct clinical manifestations was 3.7 (3.7), with the highest mean (SD) numbers of clinical manifestations observed in Italy (4.6 [4.7]) and Spain (4.7 [3.7]). Patients across all 5 countries were treated with 4 classes of therapy: oral corticosteroids (OCS; 89.3%), immunosuppressants or cytotoxic agents (63.6%), and biologics (43.9%), other therapies (10.7%). Spain had the highest mean (SD) maximum daily dose of OCS (42.4 [19.6] mg). In total, 22.9% of patients experienced a flare, and the mean (SD) number of flares in patients with ≥1 flare was 0.5 (0.3) flares/year. Patients in France, Germany, and the UK had the highest mean (SD) numbers of flares (0.7 [0.6], 0.6 [0.3], and 0.6 [0.3] flares/year, respectively). The overall mean (SD) duration of flares was 2.9 (3.2) months, with the longest flare duration observed in France (4.8 [6.3] months) and the shortest in the UK (1.6 [1.2]). Image:Summary/Conclusion: These results demonstrate that in patients with HES, there are differences in patient and disease characteristics as well as treatment strategies across Europe. These differences likely contribute to challenges in the diagnosis and management of HES and highlight the need for a common strategy to address these difficulties.